Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare destructiveHint=false and openWorldHint=true, so the description's added assurance that it 'scrolls the interface without editing its data' genuinely clarifies that viewport state changes but data does not — useful context that softens the readOnlyHint=false signal. It says nothing about failure behavior when the element can't be found, whether scrolling is animated/awaited, or how far it scrolls; with 17 parameters and an output schema, that is the level of behavior an agent would still want.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences with the purpose front-loaded and no filler; the second sentence is a genuine behavioral clarification rather than restatement. It is arguably under-informative for a 17-parameter tool, but nothing in it is wasted.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values needn't be explained, and annotations cover the safety profile. However, for a tool with 17 parameters, one enum, and three near-identical scroll-into-view siblings, the description gives no selection guidance among targeting modes or siblings, which is the main completeness gap.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so every parameter, including the id/x/y/target targeting modes, is already documented in the schema. The description adds no guidance on which targeting parameter to prefer (id vs label vs x/y vs target=window) for this tool specifically, so baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb ('bring ... into the visible viewport') and a specific resource ('identified native accessibility element'), so the action is unambiguous. It does not name or distinguish itself from the close siblings ui_scroll_into_view and browser_scroll_into_view, leaving the agent to infer the boundary.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives one useful usage cue: call this 'before reading or interacting with' an off-screen element, i.e. as a precondition step. It offers no exclusions or alternatives, so an agent facing ui_scroll_into_view, browser_scroll_into_view, or plain computer_scroll has no stated rule for choosing this one.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.